本文關(guān)鍵詞： 松江河金礦 礦床地質(zhì)特征 流體包裹體 造山型金礦　出處：《吉林大學(xué)》2015年碩士論文　論文類型：學(xué)位論文

【摘要】：松江河金礦位于吉林省敦化市,地處天山-興蒙造山帶南端,華北板塊北緣東段,夾皮溝—海溝金及多金屬成礦帶中部,成礦地質(zhì)條件優(yōu)越,是吉林省內(nèi)重要的金及有色金屬成礦區(qū)礦區(qū)地層主要出露中元古界色洛河巖群,一套高金含量的的綠片巖相-角閃石巖相的變質(zhì)巖系,原巖為玄武巖、安山巖、流紋巖以及含礫泥砂質(zhì)陸源碎屑沉積巖。礦區(qū)內(nèi)斷裂構(gòu)造發(fā)育,區(qū)域性北西向青茶館—白水灘斷裂帶斜貫全區(qū),為區(qū)內(nèi)主要控巖控礦構(gòu)造。礦體主要受近北南向次級斷裂控制。本區(qū)巖漿活動較為頻繁,巖漿巖分布十分廣泛,礦區(qū)內(nèi)巖漿巖主要有輝石角閃巖、印支早期黑云母斜長花崗巖及燕山早期鉀長花崗巖。礦區(qū)內(nèi)發(fā)現(xiàn)的礦脈主要有10條。編號為Ⅱ-1~Ⅱ-10,其中,Ⅱ-1號礦體是區(qū)內(nèi)的主要礦體,其它為次要礦體。礦石類型為蝕變巖型,局部見石英脈型。礦石礦物主要有鈦鐵礦、黃鐵礦、黃銅礦、磁黃鐵礦、自然金等。礦石結(jié)構(gòu)主要有自形—半自形結(jié)構(gòu)、他形粒狀結(jié)構(gòu)、包含結(jié)構(gòu)、碎裂結(jié)構(gòu)。礦石構(gòu)造主要有浸染狀—星散浸染狀構(gòu)造和片狀—條帶狀構(gòu)造。礦體圍巖蝕變較發(fā)育,主要有硅化、鉀化、綠簾石化、綠泥石化及星點狀黃鐵礦化等。成礦期次可以劃分為四個階段:Ⅰ石英-氧化物階段,Ⅱ黃鐵絹英巖階段,Ⅲ石英-方解石多金屬硫化物階段,Ⅳ碳酸鹽階段,其中Ⅱ和Ⅲ階段為主成礦階段。松江河金礦成礦區(qū)域上與燕山早期敦化-密山深大斷裂大規(guī)模左旋平移有關(guān)。成礦期主控礦的SN向斷裂表現(xiàn)為以壓為主的左旋壓扭特征,在斷裂走向偏左和產(chǎn)狀變緩部位為局部張開部位,含礦性好。松江河金礦成礦流體包裹體類型有:含CO2相包裹體、氣液兩相包裹體、純液相包裹體;具有低鹽度(5~9wt%NaCl.eqv)、低密度(0.66~0.72g/cm3)、中溫(173.7~345.2℃)的特點;成礦壓力84~106Mpa,成礦深度7.50~8.52km。松江河金礦成礦與空間上密切相關(guān)的中侏羅世五道溜河巖株狀產(chǎn)出的二長花崗巖有關(guān),巖漿源區(qū)為下地殼,巖石形成于大陸邊緣巖漿弧環(huán)境,成巖時代為173Ma±。礦床形成于古太平洋板塊俯沖過程中擠壓向伸展轉(zhuǎn)換的構(gòu)造背景。礦體受壓扭性斷裂構(gòu)造控制,礦石金屬礦物組合簡單,中溫、低鹽度、低密度流體和典型的富CO2包裹體發(fā)育等特征與典型的造山型金礦特征相似,按照成礦動力學(xué)背景分類,屬于中成造山型金礦。與成礦有關(guān)的侵入巖為二道溜河二長花崗巖,流體演化方面,成礦Ⅰ階段為偏高溫的氧化環(huán)境,鈦鐵礦和銳鈦礦。成礦Ⅱ階段隨著氧化物的析出,流體表現(xiàn)為還原環(huán)境,出現(xiàn)大量黃鐵礦和磁黃鐵礦,伴隨有金的析出。成礦Ⅲ階段隨著溫度降低,氣相的溢出和沸騰作用,大量多金屬硫化物發(fā)生沉淀,金的Au(HS)2-分解,大量金沉淀于石英、方解石和硫化物裂隙和晶隙中。成礦Ⅳ階段大氣水的加入流體變?yōu)橹行院推珘A性,主要發(fā)育碳酸鹽。綜合礦床地質(zhì)特征和流體演化特征,礦床成因類型為中溫?zé)嵋好}型金礦。
[Abstract]:Jilin province is located in the city of Dunhua Songjianghe gold deposit, located in the Tianshan Xingmeng orogenic belt at the southern end, the eastern section of the northern margin of North China plate, the trench - gold and polymetallic metallogenic belt, the metallogenic geological condition is superior, is the Jilin Province gold and nonferrous metal metallogenic district important strata outcropped mainly middle Proterozoic Seluohe group metamorphic rocks. A set of greenschist - high gold content of amphibole facies, the original rock is basalt, andesite, rhyolite and gravelly sandy muddy terrigenous sedimentary rocks within the mining area. The faults, regional NW - Qing teahouse baishuitan fault zone for oblique penetration of the region, the main control of rocks ore structure. The ore body is mainly controlled by the North South secondary faults. Magmatic activities in this area are more frequent, magmatite are widely distributed within the mining area, magmatite mainly pyroxene amphibolite, plagioclase granite and biotite early Indosinian early Yanshan Moyite. There are 10 main mining areas found in the vein. No. II -1~ II -10 II, which is the main orebody No. -1 orebody in the region, the other is the secondary deposit. The ore type is altered rock type, local quartz vein type. Ore minerals are mainly pyrite ore, ilmenite, brass, pyrrhotite, natural gold. Ore textures are mainly euhedral subhedral - structure, xenomorphic granular structure, including structure, cataclastic structure. There are disseminated - scattered disseminated structure and sheet - banded structure ore structure. The ore rock alteration is developed, mainly include silicon, potassium, epidote petrochemical, chloritization and star like pyritization. Metallogenic period can be divided into four stages: the first stage II oxide quartz, pyrite sericite quartz rock phase III quartz calcite polymetallic sulfide stage and carbonate stage IV, the main ore-forming stage II and III stage in Songjiang. 娌抽噾鐭挎垚鐭垮尯鍩熶笂涓庣嚂灞辨棭鏈熸暒鍖，

本文編號：1513188